The New Master Lock 5440EC Key Lock Box Safe Code Bluetooth is a portable electronic lock box made of metal with a silver and black color finish. It includes a lock box, batteries, and has a Bluetooth connectivity option. The compact size of 3-1/4" makes it easy to transport and padlock mounting ensures security for your keys. This high-quality product from Master Lock offers convenient access control and peace of mind for your business or industrial facility's keys.